BACKGROUND: Impairment of upper limb function is common in Multiple Sclerosis (MS). Rehabilitation remains a key strategy to manage symptoms and improve quality of life. The Under & Over study assessed the effectiveness of a rehabilitation programme in people with advanced MS. OBJECTIVE: To determine if repeated use of Under & Over can improve upper limb function for people with MS. METHODS: One hundred and six (N = 106) people with MS participated in this 3-month study. The primary outcome measure was the cardboard 9-hole peg test (c9HPT), with secondary outcomes including the EuroQol-5Dimensions, 5-Level Questionnaire (EQ5D-5 L) questionnaire. There were three arms: Arm 1a, the 'Daily Group', engaged with the Under & Over tool daily for 30 min. Arm 1b, the 'Free Use Group', used the same tool without time constraints, with the added feature of a community sharing platform. Arm 2, the 'Delayed Start Group', initially completed the c9HPT for three months before switching to the 'Free Use' programme. RESULTS: 43/106 (41 %) of those randomised completed the primary end point. No significant difference between c9HPT at baseline and 3 months was seen in Arm 1a or 1b. Participants in Arm 2 who had been completing the c9HPT 5 days a week for 3 months showed a training effect in the dominant hand (mean speed at baseline 0.0455 (s-1), mean at 3 months 0.0341, difference 0.011; 95 % CI 0.0080 to 0.0148, p < 0.001). No significant difference was seen in c9HPT time following 3 months of active use of the Under & Over tool. The study faced significant limitations, notably in participant adherence, with fewer than half (43/106 (41 %)) completing the final assessment. CONCLUSIONS: This study demonstrates how a small, engaged, and motivated group were able to complete a remote rehabilitation programme. Future remote intervention studies could benefit from incorporating adaptive engagement strategies, such as personalised reminders and participant-tailored activity adjustments, to enhance adherence and capture a broader spectrum of patient experiences