I think you should cut Temflex off of apples once you are sure they have taken. If you are worried about structural integrity of the graft, you can always shore it up with a stake.
@matrix calls this “cancer”, it looks kind of nasty, but did not affect the tree negatively in my case. We had a discussion about how isolation of the graft site induces undifferentiated (?) tissue proliferation on apples and pears.
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