Hi Baldur,
Have you tried graceful shutdown?
You need redundant links, but not to the same transit.
https://tools.ietf.org/html/draft-ietf-grow-bgp-gshut-06
This draft is expired, but it is actually implemented by several vendors.
I implemented this.
http://www.slideshare.net/bduvivie/bgp-graceful-shutdown-ios-xr
I added an option to configure AS-path prepends in case the gshut community was not supported by peers.
Thanks,
Jakob.