skiboot v6.3.5 was released on Thursday June 4th, 2020. It replaces skiboot-6.3.4 as the current stable release in the 6.3.x series.
It is recommended that v6.3.5 be used instead of any previous 6.3.x version due to the bug fixes it contains.
Bug fixes included in this release are:
uart: Drop console write data if BMC becomes unresponsive
core/ipmi: Fix use-after-free