But have you got travel insurance that covers this arrangement? You need to consider what happens if either of the airlines email you sometime next spring with a schedule alteration or cancellation that wrecks the plan. At least neither is likely to go bust but this far out flight plans are probably just wish lists.

Aah, steve, never really gave that one a thought ! okay, I have travel insurance through my bank account, should I ring them and enquire about this ?
cheers for the heads up on this one

I'd put money on bank account insurance NOT covering this! It's a struggle to find cover for an airline bankruptcy leaving you with a paid unusable hotel (Saga do but you have to be over 50!) and airlines just messing you about will be even harder. The problem isn't really that insurance companies are trying to avoid claims but that they haven't kept up with holiday trends and don't think about DIY. The important phrase to look for is "supplier failure cover" but that alone probably won't cover advance schedule changes and in this case you really don't need to worry about bankruptcy.

May be a better use of your time to work out a plan for what to do if either flight is retimed by an inconvenient amount.

Thanks for the advice steve, could be a case of fingers crossed !