Originally Posted by madfish

Just tried this using LHR/BCN. Using economy flights as a BA holiday then it does not give an option to upgrade. However, when booking flight only you can select one as CE and one as ET and then add a hotel. Doing it this way it then continued the booking as a BA holiday booking and therefore gave extra avios. However, not worked out the cost of this compared to doing it as CE both ways from the start. Something tells me it might be cheaper to do CE both ways. I suggest you play around with the options to see what works best price wise.