So she ran 2:25 around 40. You would need to Google what shoes, how the Melbourne course differs, and what weather and the like. But that could very well be a similiar level of performance (2-3 mins for shoes, 1-2 mins for the course, 1-2 mins for weather). Now doing it 5 years later makes it harder.
If you showed me her progression and told me it was like 20-30, I wouldn't see anything crazy. Lots of nice improvements with occasionally regressions. Most people stall out but there are always a few that keep getting better. The only shocking part is the continuing to improve post 40. Some of that is getting more training (and opportunity. Some of years are hot weather marathons).
It always feels weird to think she was clean from say 33-42 and then started doping. It is possible of course. And if she was doping earlier why didn't she run faster then?
In the end we will never know. We are left guessing if the top 10 in a distance race are as dirty as a 90s your de France, or if the doper is the exception (the guys like ramzi 3:39 to 3:30 in your mid 20s...). I hope for the former. I fear it is the later...