Flitwick emerged from three entertaining run-chases with two-wicket victories at the weekend.
The Otters initially looked up against it at home to Letchworth Garden City in the Saracens Herts League Championship, as Alan Winchester (75) and William Bates (84) put on 88 for the third wicket.
But Matt Pateman ran out Winchester, and spinners Nadeera Nawela (3-57) and George Thurstance (3-68) pounced to dismiss Letchworth for 223.
Nawela and Thurstance then combined again to add 118 for the fourth wicket, and Flitwick sneaked home at 226-8 to claim the full 30 points and climb to fifth.
Flitwick IIs remain second in Division Four A after they won by the same margin at North Mymms.
The hosts opened with 220-8 from 53 overs, with Sam Pitkin taking 3-58.
The Otters were struggling at 58-5, but Phil Gurney (53) and Rob Taylor (38) launched a recovery, before Liam Peters (35no) and Ben Barzilay (22no) finished the job at 221-8.
Flitwick IIIs had more than 10 overs at the last pair from West Herts IIIs, but could not claim the all-important final wicket in Division Nine A.
Ian Moxon-Booth took 3-45 but West Herts clung on with 110-9.
Earlier, an eighth-wicket stand of 71 between Jeremy Godfrey (31) and Stephen Allen (40) had dragged the Otters up to 181-9.
In the Greene King Bedfordshire League Premier Division, Flitwick bundled out Eversholt for 141, with Peters (4-42) and Pitkin (3-16) the main destroyers.
The Otters reached their target eight wickets down and with 21 balls to spare at 142-8.
Division Three leaders Flitwick IIs suffered a 41-run defeat at Sharnbrook.
Simon Pritchard feasted on loose bowling to make 72, as the home side made 176.
However, Flitwick never got going in a reply held up by a downpour, with James Gaul (6-48) cutting through the middle and lower order as they were dismissed for 135.
In Division Six, Flitwick III were heavily beaten by a strong Horton House side.
Flitwick skipper Robert Stanners took 2-45 with the new ball and later struck 34, but the Otters went down by 162 runs.
>> Flitwick won the Heritage Cup after edging out Potton by just two runs in the final last Friday.
Flitwick scored 147-6 in their 15 eight ball overs thanks to Henry Thurstance (35) and George Thurstance (33).
They then restricted Potton to 145-4, George Thurstance taking 2-28.