Continuing with the same tenants but with a new AST depositguard agreement

Tenancy Deposits

I have 2 tenants in a flat, the 6 month tenancy began on 29th March 2014 and is now a rolling agreement. The deposit is protected with TDS depositguard

The tenants wish to stay for another 6 months and are happy to sign a new agreement which suits me.

Their new 6 month depositguard ast agreement starts on 1 January 2015, and they will stay on in the same flat at the same rent. I am going to get them to sign a new AST starting 1 January 2015, today or tomorrow before I go away. At this time I will also give them prescribed information and “what is a tenancy deposit scheme” as well as a letter stating that the inventory is as was on 29 March and that they have received the deposit information documents.

I want to make sure that I do the right thing with the deposit protection. The timings are important

For example, should I between 1 and 10 January, unprotect the deposit for the agreement which began on 29 March. Should I then protect anew, for the agreement which begins on 1 January, and do this between 1 and 30 January? (giving my tenants a copy of the tenancy deposit protection certificate before 30 January).