Hi Julie!
What size mandrel are you using? When I make long beads, I typically use a larger mandrel (3/32" or larger) which makes it much easier to get those long beads off. Plus, it's harder to bend the mandrel.
Also, this may be a stupid question, but are your ends puckered on your long beads? If not, that also makes it hard to remove them from the mandrel without cracking.
Regarding BOM...I don't use it, but rather Sludge Plus, and I rarely have issues losing long beads. Does the olive oil not work with longer beads?
Good luck!