This grammar article says 以後 must modify some time, action, or event.
However, one of the examples is:
1) In the above example,
以後 starts the sentence and modifies nothing. Why is it okay for the first example but not this one:
2) Would removing the commas for the second example make it grammatically correct since
以后 would be then modifying
我六点下班? In other words, would this sentence -- without commas -- be correct:
我六点下班以后我去跟朋友吃饭. Would removing the comma here also make 以后 correct: