Well it seems that leaving a returning suitcase upright and partially open is most definitely an invitation for Princess.
getting out it appears she needs help.
I’m betting she waits till I’m within calling distance before she hops in to investigate as then she can let me know when she is ready to get out.
However, in future just to be sure, I shall leave the side opened too or completely zipped.
(Bet she is hunting for the soap smells hoping I’ve brought back new little packets from the hotels.)