Exponent: how to avoid that format in a text?

[Lelik]

In Plan-maker (and Text-maker), I often need to type something like “31E xyz”, but the program automatically interprets the “E” as part of a number in scientific notation and displays it as an exponent.
I can’t seem to find any way to stop that from happening. Even if I add an apostrophe before the text, or set the cell format to Text (via Format → Cell → Text), it still shows it as an exponent.
Is there any way to permanently disable this behavior, so that anything I type is treated literally, not as a number in scientific notation?