As previously announced, LMDE is switching to Debian Stable and a frozen cycle similar to Linux Mint.
The upcoming release of LMDE will be version 2, codename “betsy” and it will use a Debian “jessie” package base.
The team is currently adapting to the new LMDE, setting up its repositories and porting various packages onto it.
The target for a stable release is estimated for this November, along with an official upgrade path from UP8 to Betsy.
Beta-testing information and details will be communicated as soon as the distribution is functional. This could happen any time between now and November.