When will Project907 update to 1.13.x?"
There’s no easy answer to this question. Biggest problem is lack of updated plugins like SkyBlock but there is more. I will continue testing as more stable versions of 1.13 become available but we will continue running 1.12.2 until further notice.
Read about Spigot https://www.spigotmc.org/
Outdated essential plugins like SkyBlock. Changing plugin to another will more likely make old world unusable. It is better to wait for an update than install something that may destroy your work.
Chunk errors may occur when old map is updated to new version. These are results of testing 1.13 October 4th 2018
Server is working 100% as is. Please use game version 1.12.2 and have fun playing. More information is coming later...