I wasn't thinking so much 'signs' of 2-1 just yet, more that it's coming yk...most of these things caught be totally unaware when I went through them with DS and I'm more mindful now that if there is one shorter nap with one good long nap then really that's going to be ok, you could tweak and tweak trying to get two long naps and then a week later they are 'suddenly' 9 or 10 months and refusing BT or having cot parties because they have too much day sleep.
Sounds like you need to go with the flow a bit whilst you have holidays etc.
Hope it goes best it can for you xx