Life span of frozen cell??

So I had an embryo become a blast this morning and it was a 2bc grade. Anyway I had them biopsy it and freeze the cells in case I don't get a positive from this cycle I will have the option to run pgd (batch it ) with another fresh cycle in the future. My question is how long are these cells able to be frozen for? I ask cuz I think someone on here told me I would have to test them within a few months of freezing which if that is the case I most likely tampered with this embie unnecessarily. I would probably not be testing it for 5 or 6 months if I do another fresh cycle. Am I making this up or did someone tell me this before? Does doing a biopsy on this quality of embryo risk it further? I feel like I just tampered with it for no reason. Ugh!