Update as of April 26th, 2018 - This issue has now been resolved and customers and partners can resume environment deployment in their own subscription. However, any submitted requests for environment deployment in implementation projects will resume slowly.
We are aware an issue in LCS that is causing DevTest and Build environment deployments that were started in Implementation (customer) and Partner Projects to fail with an unknown exception.
Do not schedule any deployments for these topologies until this issue is resolved. The engineering team is working on releasing a hotfix. This issue also impacts all current requests for environment deployments for DevTest or Build topologies in customer implementation projects. Those deployments will resume after this issue is resolved.
This blog post will be updated when the issue is resolved.