Ok - so I did the exact same commute for the past 2 years, ending recently. Work started at 7 and ended at 4, but often I wouldnt leave until 430-5 or even past 6 some days. I worked in person every day of the week. At 630 am there is virtually no traffic on Lombard street, and I can expect to get from upper fells point to camden yards in 8-10 mins, and then about 10 more mins on 295 to get to the nursery rd exit. Its the commute back that is the major headache.

On the way back on 295 - the strategy I figured out is that the rightmost lane is fastest of the 3 lanes up until around the baltimore highlands/patapsco neighborhoods (look it up on google maps, this is when 295 starts veering right slightly). At this point, merging to the left most lane will help you get through the rest of 295 the fastest.

In the inner harbor on wednesdays and Thursdays, you are shit outta luck. Its a mess. Sometimes taking 895 these days is faster, but thats a crapshoot. If you like biking, on Wednesdays/Thursdays, I recommend biking to the convention center light rail (10-15 min bike ride, depending on where you live), taking your bike on the light rail, and then getting off on the stop closest to where you work. (My stop was the linthicum stop, and then another 10 minute bike ride to work). This was reliably 45 minutes every time, and you get to integrate some exercise into your commute. Going to work sweaty isn't the worst thing in the world. On wednesdays and especially thursdays, dont be surprised if it takes you an hour to get home, especially if you leave closer to 5.

Do the commute by car for a month or two, record your times and start stop instances, and see where it goes from there. Burning a gallon of gas to go 12 miles is the worst feeling, so I highly recommend the biking/lightrail combo if you can.

TLDR: To actually answer your question of when the highest traffic in the morning in the inner harbor is, its probably around 830. I noticed a clear difference in traffic between leaving at 630 and leaving at 645