Up to u.. a few mths prior will be good enuf..if ur child is a toddler he/she may take some time to adapt to the routine and u wont know how long he/she will cry when u send.. u will also nd to gauge ur timings in the morning how long u will nd to get ready for work/sch in the morning n the journey to work after that etc etc..
Stranger anxiety kicks in around 7-10 months, and separation anxiety comes in after that (around 1 yo), so you can take these into consideration when deciding on when to enroll:)
Thanks for the advice