It's good that you recognized the change in your CRA status this early. I'd like to leverage off of Len S's comments and add a piece of advice.
First the advice: contact your examiner and invite them to a meeting at your bank to discuss with you how life under CRA will change as an ISB. Chances are they, or someone in that regulatory agency, already have a presentation that covers this. I suggest that major bank decision makers, not just compliance staff, attend this meeting. That means the CEO and the chief investment officer, at the least, as the bank will have to be cognizant of community development lending, investments and services under the ISB test. When you cross over to large bank status, I suggest adding the chief IT officer to the mix, too, as they'll have to devise the method of collecting lending data.
And now to leverage off of Len's comments: Your lending performance will still be judged via the small bank CRA test, i.e., loan to deposit ratio, lending in the AA, geo and borrower distribution, and response to complaints. What the ISB test adds is the community develop test. Get intimately familiar with the regulation's community development definition.
From that you'll see that your garden-variety investments won't garner you any CRA credit. This lead time you've given yourself, and the chief investment officer, is plenty in which to revise the bank's investment strategy, and identify and acquire qualified investments. Same thing with CD lending and services, which is where the CEO and chief lender may come in.
Your anticipation on tnis should bode well for you, avoiding the pitfalls that unprepared banks have experienced when their examiners show up for their first ISB exam and find little or no CD investments or services. Good luck. AR.