All the hybrid seed you buy is F1. That is because the seed is 100% predictable (except for rare mistakes) when you cross two stable parents. Every plant in the F1 should be and usually is identical. Yes you can grow out an F1 for seven generations and make it stable, but it will never be exactly like the F1. Also yes, all heirlooms are 'open pollinated' which is a term that really means "self pollinated for generations until stable".
Also you may have mistaken me, I didn't mean that the fruit from your plants growing now will be different because bumblebees cross pollinated them. That's not the case, they should be what they are advertised to be. Only the seeds of the fruit are affected genetically by the bumblebee cross, so if you save your own seed from a crossed fruit, the plants you grow next year will be a cross of some kind and not the same as the parent plant that the seeds were taken from.