I did my six trips in one day. Since BAL-BWI is a pretty short leg and generally not an origin or destination, I got scanned heading out of BWI, but from BAL I had to get my ticket scanned on the platform at BWI a few times, but none of the conductors were bothered when I asked.
The AGR transaction history very helpfully marks each nth trip towards the challenge. All six trips posted about 48 hours later as expected. Five of the trips counted, for some reason, one did not. (It was the only one I had reserved round-trip, after making that reservation, I realized I could reduce my wait time by booking one-ways since the round-trip option wouldn't let me book return trips less than 45 minutes after arrival. As much as the BWI rail station has improved, I did not want to stay there any longer than necessary as it doesn't have Wifi, it's in a bit of a cellular dead zone, and it's actually busier than Baltimore Penn Station at times.) However, I had more Amtrak travel coming up, so I did not try to raise any issue with AGR about the missing sixth trip.
I just had my sixth trip this week, and in about 48 hours, it got marked as my sixth trip towards the challenge, and about 24 hours after that, my profile shows Select status, expiring 2/29/2024, and a bunch of new coupons. Was it worth the ~$150 in trips? Probably, considering you'd normally have to spend ~$2,500 to get the same outcome.
Also, I disagree with Miles, I'm pretty much addicted to Acela (Business or First) at this point, when I'm traveling with a larger bag, there's always room for it, and when I've ridden FC on a short trip (WAS-BAL and even BAL-BWI) the car attendants are still more than happy to ply me with food and drink.
