So I was reading through A Dictionary of Basic Japanese grammar and I noticed a strange contradiction in the たら and あとで entries.
In the あとで entry we see the following note:
Vinf·past ato de can be replaced by Vinf·past ra when the latter is used with a purely temporal meaning (i.e., ‘after’, ‘when’).
Then it lists following examples
Now when we look at the たら entry:
When S2 in “S1 tara S2” represents a past action, the action cannot be one intentionally taken by the agent after the action or event represented by S1.
When I look back at the examples in the あとで entry, I see that examples b and c make perfect sense and follow this rule correctly. However, sentence a looks to be a volitional act.
I asked a native Japanese speaker and they said that it is correct because すぐ is after たら.
I'm quite the beginner so I might be missing something obvious. Can someone explain to me why すぐ makes this sentence valid?