I have a feeling that whatever you're using to estimate your calorie expenditure is over-egging it if you've moved into a maintenance level of calorie intake.

I did have a plateau but I started trying to lose weight, and start running at the same time. I started by setting my calorie goal far too low to be sustainable and ended up not making the progress that I'd anticipated. Given your profile commentary I don't anticipate that applies to you.

As far as progress is concerned, taking an extra two weeks so far isn't a big deal. Better to make progress steadily than damage yourself, particularly given your profession, the last thing you need is a leg injury.

Sounds like you're over estimating your expenditure then.

And from your profile it looks as if you're used to training, so you're only new to running.

One of the problems that people encounter is that your HRM might include your BMR calories in your exercise calories. Since MFP already gives you these calories, you'd be counting them twice. That's why a lot of people only eat back "half" of their exercise calories.

Personally, I estimate a flat 100 calories/mile of running. It might not be perfect, but it works enough for me to be able to meet my fitness goals.