NAV sag of 64 bps on Fri 8/27 would seem to imply DBLTX went ex then. No word on the Mstar website though so this could be some sort of mixup with either Mstar, Double Line or the reporting services. If you bought on 8/27 be sure to monitor the action to make sure you get the divi.
I had assumed that the fund would go ex dividend on the last day of the month and that Friday's $.07 drop was because of the big selloff in the bond market. But based on the information at the link it appears the fund went ex dividend on Friday, the date of record was Monday and the dividend will be paid on Tuesday. If that's the case it looks like the fund was flat or up a penny on Friday net of the dividend. I don't know how he managed to avoid a hit on Friday and then go up $.05 today when rates went back down.
Gundlach manages for total return rather than to maximize the current dividend payout, so I expect that the monthly dividend could go down a little when he repositions the portfolio. I think most of the yield of the fund is coming from non-agency mortgage securities and he hasn't suggested he is close to selling those. He was quoted recently as saying he thought the downward move in interest rates over the last several months was about 80% done, which suggests he may be selling some of the 30 year treasuries he's had in the fund for duration. He is having a webcast on September 14 to provide an update.