08 and 09 are not valid numeric literals because the 0 prefix designates an octal (base-8) number.
01-07 work fine because that is the very same number in octal and decimal, but they are still octal numbers as well.
PHP up to and including 5.6 would only report this as a warning level error, but as part of a major redesign in PHP7 and because this could cause really strange behavior when not noticed and performing calculations (i.e.: 07+08 is not 015 but 07 and 070 + 015 is not 85 but is 69 and 0105)
Check out my post linked in the FAQ
for info on how to fix this yourself or upgrade to at least SAM 2018.3 to have Spacial fix this for you. (The code is the same since Spacial just shipped what I sent them)