Ending a Periodic Tenancy early - advice please?

I've had great tenants for almost two years but recently the flat has had some unavoidable leaks.

To cut a long story short, my tenants have agreed that the best course of action is to find alternative acommodation (they've already put down a holding deposit) so that I can get contractors in through the insurance to replace the flooring etc. Very understanding and good of them....

But, with regards to ending the tenancy early - are there any steps that I MUST follow to avoid any future issues, not that I would expect any - but I want to make sure I do things properly?

In an ideal world we'd agree a date of them moving out and I'd forward them their deposit back - is this ok to do?

Look forward to your thoughts?

Thanks,
Simon