Thermometer: digits increase, starting from the bulb.
Blue dots link cells with two even digits.
Red dots link cells with two odd digits.
Yellow dots link two cells with one even and one odd digit.
Do you like the (for me new) rule with the colored dots? This is an easy puzzle version to test it. Please leave a comment, and if well-liked, I'll write more (and more challenging) Sudokus with that ruleset.
Sudokupad: Link to Sudokupad
F-Puzzles-Link: F-Puzzles link
PS: if you like this puzzle, please also see my other Sudokus with month names:
Solution code: the bottom row