I personally would not do time outs at that age ... from what you have shared it sounds like IMO she is biting because she lacks the language and skills to manage her frustration .... so how does 'punishing' her with a time out help to teach her either of those things and it does not keep the others 'safe' because they are already been bitten?

When a child is learning to walk and they fall over and knock down another child in the process we do not 'punish' the child who is learning to walk ~ we accept that it was a honest error, the injury to the other child was not 'intentional' and we comfort everyone and point the budding walking in the other direction with the 'be careful watch for your friends' reminder ... we do not pick them up and put them in a confined space because they might 'knock over another child' in their effort to learn?

Dealing with biting in a toddler is no different IMO ... the child is still wee and as a result in a state of 'fight or flight' response in that moment of feeling frustrated and frightened about whatever is occurring ... and because they are still learning to communicate, to express themselves in socially acceptable manners and so forth they do not INTEND to hurt another person they are applying a 'basic need' strategy imbedded in our brains that works ... when in that state of 'fight or flight' due to an emotional trigger biting someone protects themselves or their perceived belonging or space and causes the other person to move out of their space and so forth ... there is nothing MORE to it than that ... it is not malicious or thought out to purposefully 'hurt' someone else with planned intent it is an impulse they are fighting in a split second decision of how to I make myself feel 'safe' again!

IMO we need to teach them better strategies to control their impulses and engage the 'flight or fight' aspect of the brain with more socially acceptable options in our now 'evolved' state of being ... punishing them for acting on a basic need to protect themselves is just going to leave them feeling confused and their self esteem bruised because try as they might the next time they are going to repeat the behavior until they have a 'better option' they are going to revert to that basic need brain wiring

Attach something to their clothing to 'bite' instead .... a soother, a teething ring, a cloth or whatever works for them as a 'surrogate' ~ when they DO attempt to bite redirect them 'when your frustrated bite this ~ we do not bite people' verses telling them 'We do not bite' because the reality is in that little fight or flight moment they are having they NEED to bit something to relieve their state of frustration ... it is like telling them 'do not breath' and expecting them to comply ~ when the next moment arises when they 'need to bite' they will remember 'bit this' and train the brain to do that instead!

Reduce the opportunity for 'frustration' to arise by reviewing the program and minimizing transitions, waiting times, getting additions of popular toys items that are a communal source of frustration in the group and so forth. When know you are going to be 'busy' and not able to be there to support a biter in the group than BEFORE they make a mistake and bite someone as a result set them up in a safe place to prevent the biting in the first place ... so not a 'time out' after the fact as punishment but having them be your 'helper' and holding the diaper or wipes while you change a diaper, setting them up with coloring or something in the kitchen while you prep meals, putting a special invitation in the pack n play and giving them a 'turn' while you go to the bathroom and so forth ... so the child is being set up to 'succeed' in not biting during those times while the other children are being 'protected' from being bitten.

Than at other times of the day you can focus on increasing the 'supported' practice of sharing and taking turns by providing invitations in the program that encourage these skills to emerge at times of the days when you can 'be there' to support proper language and social skills for handling any frustrations that may arise before it gets to a biting stage ... so for example set up a play doh invitation where only TWO children can play so the others have to learn to 'wait' their turn and than AT the play doh invitation set out only one rolling pin and so forth to encourage 'turn taking' with it ... stay close by and see how they manage and if a frustration struggle ensues you step in before it escalates and role model how to resolve it with words and language.

These are strategies I use to prevent 'biting' in my program from even starting in the first place ... 6 years with no biting incidents!