Last year we did a Halloween Sailing right at the start of the season. We saw Jack and Sally walking around, but never actually saw a chance to take pictures with them (This was most likely due to covid restrictions)
They did have them appear for the Nightmare before Xmas sing along in the WD theatre, but that was a "Smile and wave"
Hopefully they will do actual meet and greets this year, Usually I think they recommend showing up about 15 min early for characters?