Erasing files before last update may result in massive unrecoverable loss of date. This is one for your worst case scenario. No idea if this is a problem but it appears to be in the danger zone. 4.3.3 Network timers Overruling PC timers and forgotten by the overloaded operator. They will skip the leading spaces, or take more space when the 20 is inserted.
Line wrapping makes a mess of it.
The same goes for terminal screens. These will have problems earlier. They may have already been repaired before you formulated your YEAR2000 modification strategy. These problems have been reported as early as 1970. It is easy to forget one of these.