I don't think his body would take all that flying - 11 hours twice a week & the jet lag

. Come on he is nearly 80.
Len imo got grumpy & harsh last year toward the end of the series when he was obviously tired & he's only 65!
Would you want your Dad at 80 doing two stressful jobs & flying backward & forward over the atlantic? I would n't want my Dad doing it now, he's fit too & only 70 but I'd be worrying myself sick about DVT's, strokes etc.