My knowledge of upgrade 3.6.x. to 3.8.x (12 month period) is a testament as to why an LTS, with more complete QA (or at least full documentation) should be on Koha's horizon (and to pre-empt comments concerning why I should search git and bugs and wiki and INSTALL (all variants deb, ubuntu, bland) and community and devel and users and download and ... I'm sure you understand.)