What about the 17.4 days thingy
That was just the 1701D. The Bozeman just came through once. The 1701D was hit numerous times because it kept going back in time.
1. The Bozeman enters a space time distortion and exits it.
2. The 1701D enters the Typhon Expanse.
3. The 1701D enters the edge of the distortion.
4. The 1701D looses power.
5. The 1701D sees the Bozeman coming out of the distortion.
6. The two ships collide.
7. The 1701D explodes.
8. The 1701D returns to step 2.
That still doesn't work out, for a few reasons. When the Enterprise finally breaks out of the time loop, the computer's chronometer is off from the Federation time-base beacons by 17.4 days. Now, If the Enterprise travelled back in time, they would have ended up breaking free of the loop at the exact moment they were destroyed
the first time, and their chronometers would be perfectly in sync with the rest of the Federation. The only way for the chronometers to be off would be that the chronometers are reset along with the rest of the ship after the explosion, but they stayed in the current time. For example:
Say the Enterprise exploded the first time at midnight, the ship gets reset to what they were 6 hours previously, but it is still midnight. 6 hours later they explode again. Their clocks would say midnight, but it is actually 6am. The ship is reset to the way it was 6 hours previously(which was really identical to the way it was 6 hours before that), but it is still 6am. 6 hours later they reach the point where they explode again, their chronometers still say midnight but it is now in fact noon. Their chronometers would, at that point, be off by 12 hours. This continues until they have been offset by 17.4 days.
Your way would turn out like this: The Enterprise explodes at midnight. They travel back in time 6 hours so it is now 6pm. They continue on unaware and 6 hours later they explode again, and it is once again midnight. They travel back in time 6 hours, to 6pm. They continue along unaware and they once again explode at... Midnight. They eventually break free and it will be midnight, the exact time they first blew up, and they would be right on track with the universe. The only way for them to be off by 17.4 days your way would be if they went back in time but their clocks didn't reset when everything else did. But then someone would notice that the clocks were off...
The second reason that wouldn't work is the way they broke free of the loop. Data sends himself a message by imprinting it on the surrounding dekyon field. Data did this just before the ship was destroyed. Now, if the Enterprise was traveling back in time, like you say, then for Data to subconsciously pick up the imprint in the dekyon field, the dekyon emission Data sent just before the destruction would have to have also traveled back in time with them... However, that doesn't really seem to be the case here, as they compared the dekyon field imprints to "echoes"...
It really seems to me that the events were repeating and happening multiple times in one stretch of time, rather than the Enterprise moving back in time and merely reliving a single event.