To my reading, everything about Paul's letter to Galatia suggests it was written after the Council of Jerusalem. It baffles me that many conservatives hold the opposite view. I hope some of them will read the rest of this post.
Galatians 2:1-10 cannot refer to Acts 11:30 for two reasons – chronology and logistics. Paul and Barnabas cannot travel over 350 miles from Antioch to Jerusalem in the middle of a famine with several wagons full of grain in a caravan conspicuously large enough to feed the entire church in Jerusalem for over a year. Aside from the trouble, not to mention the risk, the expense of oxen, carts and handlers for transit would have been much more appropriately spent on additional grain. More importantly, Antioch knew when the famine was coming. If we accept Agabus’ prediction as historical, the church in Antioch had plenty of time – not only to save up the money required, but to take that money to Jerusalem in advance. Bringing money to Jerusalem instead of grain would require that it arrive well in advance of the famine, so that the church could begin stockpiling grain gradually, without drawing too much attention.
A plain reading of Acts 11-12 suggests Paul and Barnabas’ delivery occurred in early 44 AD, before the first harvest, giving the church plenty of time to begin buying up grain. Since Galatians 2:1 refers to a visit that occurred “after an interval of 14 years”, the conversion of Paul would have to take place in 27 AD (or 30 if one includes the three years in Arabia as part of an overall 14 year span). To my knowledge, no one has suggested Paul was converted so early, and I suspect no one ever will. Indeed, Paul’s conversion fits best in 34 AD, which leads some to posit an inclusive 14 year span culminating in a massive delivery of physical grain during the first or second year of the famine itself (47 AD). Of course, this postulation also requires an otherwise pointless (and otherwise baseless) reconfiguration of the chronology around Acts 11:30 and 12:25, as if those two verses alone happened three years later than everything else mentioned in between.
In my opinion, the discombobulated chronology is as impossible as the logistics of delivering relief ‘in kind’. The only way Antioch was able to feed Jerusalem is if the money got there in advance. As a conservative, I take on faith that Agabus did indeed prophesy the famine in advance. What I do not know, is why many of my fellow conservatives seem so loathe to consider Paul writing Galatians after the time of Acts 15. I suggest Christian scholars consider embracing the fact that James & Paul continued to have conflict after the Council of Jerusalem. It should be far easier to adapt theological interpretations of that disagreement to preserve the integrity of scripture than to bend time, space and physics so that we can all imagine James & Paul learned to play nice. (And if that is not the problem, please tell me what is.)
Incidentally, if this view causes the historicity of Acts even partly to stand or fall on the acceptance or rejection (notice I do not say ‘probability’) of Agabus’ forecasting ability – then so be it. IMHO, New Testament scholarship ought to be more that way anyway.