TemplateRegexMatcher.getStartRegex sometimes returns a regex that matches with an index before the license start

Version 1.1.11
Example 1 greedy regex after optional:

String licenseText = "ab cd text";
String licenseTemplate = "<<beginOptional>>cd<<endOptional>> <<var;name=\"copyright\";original=\"Copyright (c) <year> <copyright holders>  \";match=\".{0,5000}\">> text";
TemplateRegexMatcher templateRegexMatcher = new TemplateRegexMatcher(licenseTemplate);
String startRegex = templateRegexMatcher.getStartRegex(25);
System.out.println("start regex: " + startRegex);
Matcher matcher = Pattern.compile(startRegex).matcher(licenseText);
if (matcher.find()) {
    System.out.println("start index found: " + matcher.start());
}

Returns

start regex: (?im)(\Qcd\E\s*)?(.{0,5000})\Qtext\E\s*
start index found: 0

but the start index should be 3.

Example 2 greedy regex at start:

String licenseText = "abtext";
String licenseTemplate = "<<var;name=\"copyright\";original=\"Copyright (c) <year> <copyright holders>  \";match=\".{0,5000}\">> text";
TemplateRegexMatcher templateRegexMatcher = new TemplateRegexMatcher(licenseTemplate);
String startRegex = templateRegexMatcher.getStartRegex(25);
System.out.println("start regex: " + startRegex);
Matcher matcher = Pattern.compile(startRegex).matcher(licenseText);
if (matcher.find()) {
    System.out.println("start index found: " + matcher.start());
}

Returns

start regex: (?im)(.?{0,5000})\Qtext\E\s*
start index found: 1

but the start index should be 2.
.?{0,5000} doesn't seem to work as expected. It is an unusual regex that some online regex websites say is invalid: https://regex101.com/r/l3810b/1, regexr.com/81kfo.
https://www.freeformatter.com/java-regex-tester.html says the regular expression is valid.

I think maybe to fix this you could just offer a method for a regex to find the beginning of the non-optional part. Otherwise a changing the regular expressions in these two cases to something like the following could work

(?im)((\Qcd\E\s*)(.{0,5000})\Qtext\E\s*)|(\Qtext\E\s*)
(?im)\Qtext\E\s*

In the first case if there were multiple optional parts it would get even more complicated to do it correctly.

Start with TemplateRegexMatcher.getStartRegex and reproduce both Java examples from the issue. Trace how optional sections and greedy variable matches are converted into the start regex; done means the examples report start indices 3 and 2, including correct behavior when optional parts are present.