This is more of a technical ruling based upon procedural requirements by the E.P.A. known as the Administrative Procedures Act that requires a 30 Day waiting period before finalization. Sounds much like they can still do it if the new E.P.A. Administrator follows that rule but until then the Obama enhanced rules remain as they were. It will obviously give the LEFT ammunition to say that this Trump Administration is ‘lawless’ but otherwise it looks like this injunction will be temporary.
On the other hand there is a similar suit in New York State brought by 11 state AGs (all Democrats) for much the same thing. Differing decisions at different Federal Courts is an almost direct line to the US Supreme Court.
All comments have to be addressed which sometimes means revising the rule.
No doubt this is why Trump shortened it so as to prevent comments from being made.