I was thinking the same thing, but like Rodney I'm not actually a heat press guy either.
Is the white actual ink? When it's transferred does it leave only the design, and not transfer the paper? If so, it would be either a plastisol transfer, or a dye sublimation transfer (have they carried white ink across to dye sub? or only DTG?).
I'd check how long it should be pressed first. If you search the forums you can probably find how long people usually press plastisol transfers for, or if you go to one of the sites that sell them (also listed on the forums) they may have instructions. Probably better to find out what a typical pressing time is first, just in case it differs.
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