I have identified some typos/errors:
There should be an "and" instead of an "ad"
There should be a "with" in between "interfere" & "the"
"explicable" should be "explicably"
I understand why the WW1 & WW2 eras were left out. (you know to leave out stuff for the future). The one critique that I actually have for the timeline, is that it has no mentions of any pre-MI13 occult groups/organizations. Because I really doubt that there were no noticeable minor organizations in Britain. (But hey this looks like we can explained away with the presence of the authority or something.)
Overall it's okay 👍 (just need some future expansions, that's all).
btw I'll be editing out the mistakes if that's cool.