Sticky bark on brisket....what happened?

I tried some new things on a packer I smoked yesterday. It came out pretty good, had a lot of flavor but the bark was sticky. It stuck to the butcher paper and it was hard to cut. The bark was really crunchy but tasted good.

I used butchers prime injection and dizzy pigs rub. I feel like maybe one of those has some sugar in it that turned hard.

Any ideas from guys that have used either. It was my first time for both

Cooked at 250 grate temp. Kicked it up to 275 the last 2 hours. It was the DP cow lick

I’ve cooked more than 10 prime packers from sams and haven’t had it happen before. Could it just be certain briskets that have “sticky fat”.

The bark also came out more tough than usual