On the subject of the $150 redeposit fee:

I'm a GM, booked a domestic award ticket in Y at Low some 7 months out. I would have liked to have booked F, but only High level was offered.

Fast forward a few months and Low level F is now available. I enquired about moving up to F and burning some more miles, was told it was certainly doable, but I'd need to pay the $150 fee.

I'd suggest either of the following two options for consideration by Delta:

1. In cases where GM and FO are upgrading or using more miles for the new itinerary, consider a policy change whereby redeposit fees are waived when it is an upgrade to either a higher class or a higher level of miles (e.g. change from Low to High or Economy to First)
2. In the alternative, consider offering a discount on the redeposit fee of $150 for GM/FO irrespective of change being made. Similar to Economy Comfort, perhaps $75 for FO and $50 for GM?

In my case, Delta enjoyed the benefit of holding back F inventory for several months giving them the opportunity to sell that inventory. The fact that it has not sold and they are now offering it at low award level is great, but I'm now stuck paying $150 if I want to get it. Doesn't really seem too fair, especially as a GM.