Interested to see that Mandy is entered here in the US$25k clay court, where she may be #2 seed, rather than the $80k clay court event on the same week in the US, where Tara is entered. Mandy would have made the main draw of the $80k event, and since she's entered the Charleston WTA qualies this week, am surprised she's stepping down quite so far next week...
I think geography comes into it; Mandy's entered into a 60k in the following week in the same US state (AL=Alabama) as this 25k. The 80k in Florida would be about a 1,000 miles extra round trip.