I think that should be fine. Automatic revalidation applies even when the non-immigrant category changes. A change in the details of I-20 should therefore not be a problem.
See 22 CFR 41.112 (d) (1) (ii):
d) Automatic extension of validity at entry points.
(1) Provided that the conditions set out in paragraph (d) (2) of this section are fully met, the following provisions shall apply to non-immigrant aliens applying for readmission at points of entry:
(i) The validity of an expired non-immigrant visa, issued in accordance with INA 101 (a) (15), may be considered automatically extended until the date of application for readmission; and
(ii) In cases where the DHS has changed the non-immigrant classification of a non-immigrant to another non-immigrant classification, the validity of an expired or unexpired nonimmigrant visa may be considered as automatically extended on the date of the readmission application, and the visa can be converted as needed into this modified classification.
(2) The provisions of paragraph (d) (1) of this Division apply only in the case of a non-immigrant alien who:
(i) is in possession of a Form I-94, Arrival-Departure Record, approved by the DHS to indicate an initial admission period or extension of the unexpired stay, or, in the case of 39; a qualified F or J student or exchange visitor or the accompanying spouse or child of such a foreigner is in possession of Form I-20, Certificate of 39 eligibility for non-immigrant student status, or Form IAP-66, Certificate of Eligibility for Visitor Exchange Status, issued by the institution where the student has obtained has been authorized to attend by the DHS or by the sponsor of the exchange program in which the foreigner has been authorized to participate, and endorsed by the head of the institution or sponsor of the issuing program to indicate the period of initial admission or extension of stay authorized by DHS;
(ii) requests readmission after an absence of not more than 30 days in an contiguous territory or, in the case of a student or an exchange visitor, a spouse or other a child who accompanies and complies with the provisions of paragraph (d) (2) (i) of this section, after an absence not exceeding 30 days in contiguous territory or adjacent islands other than Cuba;
(iii) maintained and intends to resume non-immigrant status;
(iv) applies for readmission in the period of initial admission or extension of the authorized stay;
(v) is in possession of a valid passport;
(vi) Does not require an admission authorization under INA 212 (d) (3); and
(vii) has not applied for a new visa abroad.
(3) The provisions of paragraphs (d) (1) and (d) (2) of this section do not apply to nationals of countries identified as supporting terrorism in the Department's annual report to Congress entitled Patterns of Terrorism Global.
See also 8 CFR 214.1 (b) (1) (iv), which is specific to I-20 requirement for F-1 students:
(b) Readmission of non-immigrants under Section 101 (a) (15) (F), (J), (M) or (Q) (ii) in order to complete non-immigrant periods past admission or extension of stay –
(1) Section 101 (a) (15) (F). The reinstating immigration officer shall reinstate, for the duration of the status defined in paragraph 214.2 (f) (5) (iii), any non-immigrant alien whose non-immigrant visa is considered to be automatically revalidated in accordance with 22 CFR 41.125 (f) and requesting reinstatement of section 101 (a) (15) (F) of the Act, if the alien:
(i) is eligible;
(ii) requests readmission after an absence from the United States of not more than thirty days in contiguous territory or adjacent islands;
(iii) is in possession of a valid passport except where he is exempt from the obligation to present a passport; and
(iv) Presents, or is the accompanying spouse or child of a stranger, a Form I-94 (see § 1.4) of departure and departure registration issued to the 39, foreign in connection with the admission or previous stay, the form of the foreign I-20 ID copy, and either:
(A) One page 4 of the I-20A-B form duly endorsed, if the information on the student's last I-20A form has not changed since the publication of the form; or
(B) A new I-20A-B form has been a major change in information from the last I-20A form of the student since the publication of the form.