A warm welcome to this forum @JohnIoM - hopefully someone with similar experiences will respond to your post, but I also wanted to let you know of this thread started by someone with APL, Hello New diagnosis of APL Leukemia - Recent diagnosis - Blood Cancer UK Forum
and also, here are all the threads which talk about relapse, just in case you want to join any,
Search results for ‘RELAPSE’ - Blood Cancer UK Forum
We’re only a phone call away on 0808 2080 888 if there’s anything we can do to support you.