Still racing in the WEC as well, so:
Mexico Grand Prix This Weekend, WEC Shanghai next weekend, Brazilian Grand Prix the weekend after that, WEC Bahrain the following weekend then finishing off at the Abu Dhabi grand prix.
Because of all the commitments of a race weekend and practice for the WEC starting three days after each Grand Prix Hartley is literally going to have at most 24 hours to get from one continent to another and recover from his jetlag, etc.
It's a shame they couldn't just replace him in the WEC, one of the Porsche teams will win it either way, and let him concentrate on F1.