While i have not hatched pea eggs i have hatched lots of other birds.
If it were me i would wait till this evening and if it is still like that i would help it out.
Here's what i do, run a sink of warm water and have some warm towels from the dryer waiting, i submerge the shell in the waster at gently spoon water around the inside of the shell being careful not to get water around the beak area, i then start chipping away the shell only and watch for bleeding, if all goes well by time you get most of shell off it should be moist enough to drop right out in your hand out of the membrane, i then place them in a warm towel and back in the hatch-er to dry.